Jun 18, 2010 1:12 PM

Which Haematopota species is this? Chinery talks of a difference in the "more or less rectangular cell in the centre of the wing", from which I incline towards pluvialis, but what does crassicornis look like? Are there other differences? Are the eye patterns the same? Many of the web illustrations are dubious in identification. This is a swotted and stunned female, that was about to bite me. West Sussex, Weald Clay scrub, 17/06/2010, where a great nuisance!

I'm afraid I can't really add anything intelligent to the crassicornis / pluvialis debate..... but I can compliment you on a wonderful picture and whilst we await illumination from someone with appropriate UK knowledge, I might direct you towards a debate at 'Diptera.info' where http://www.diptera.info/forum/viewthread.php?thread_id=23546 has some interesting comment and images around this very topic...... Enjoy

I'm not much of a Dipterist but there is some interesting information, and a key to the genus, in Verrall's British Flies, on p. 328. Fortunately this rather rare volume is now out of copyright and available in the internet for free download as a PDF. http://www.biodiversitylibrary.org/item/36929#10. While you are there you can get Fowler's Coleoptera and Morleys' Ichneumonologica and be all set for a wild night in.

it is probably H. pulvialis. This is a common fly and is browner than the H. crassicornis. There is an excellent book called British Soldierflies and their Allies by Stubbs and Drake which deals with this family of flies.

I downloaded Verrall's book which has highly detailed descriptions of these species, both sexes. From this I am sure it is pluvialis. A key feature is the presence of a rusty colour to part of the antenna as opposed to completely black. This does not show up too well in some photographs because of lighting, but tweaking the levels in a photo editor should reveal it (or not). All of my photos of clegs are pluvialis, including a male. They are all from the same locality. Incidentally, Verrall describes his personal progression through the week of the aftermath of a cleg bite. In general I react similarly. They are sods!